2015/04/16 by V. Bourrier, A. Lecavelier des Étangs, Bourrier, Vincent +25 · 1 citation
Physics and Astronomy · #Astro and Planetary Science #Astronomy and Astrophysical Research #Earth and Planetary Astrophysics (astro-ph.EP) #FOS: Physical sciences #Stellar, planetary, and galactic studies
paper · pdf · doi:10.48550/arxiv.1504.04130
openalex publication_date 2015/04/16 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We present the detection and characterization of the transiting warm Jupiter KOI-12b, first identified with Kepler with an orbital period of 17.86 days. We combine the analysis of Kepler photometry with Doppler spectroscopy and line-profile tomography of time-series spectra obtained with the SOPHIE spectrograph to establish its planetary nature and derive its properties. To derive reliable estimates for the uncertainties on the tomographic model parameters, we devised an empirical method to calculate statistically independent error bars on the time-series spectra. KOI-12b has a radius of 1.43±0.13 RJup and a 3σ upper mass limit of 10MJup. It orbits a fast-rotating star (vsini⋆ = 60.0±0.9 km s-1) with mass and radius of 1.45±0.09 MSun and 1.63±0.15 RSun, located at 426±40 pc from the Earth. Doppler tomography allowed a higher precision on the obliquity to be reached by comparison with the analysis of the Rossiter-McLaughlin radial velocity anomaly, and we found that KOI-12b lies on a prograde, slightly misaligned orbit with a low sky-projected obliquity λ = 12.6\stackrel+3.0-2.9^∘. The properties of this planetary system, with a 11.4 magnitude host-star, make of KOI-12b a precious target for future atmospheric characterization.